Measurement of the anomalous like-sign dimuon charge asymmetry with 9 fb-1 of pp collisions

Authors

V. M. Abazov, Joint Institute for Nuclear Research, Dubna, Russia
Kenneth A. Bloom, University of Nebraska-LincolnFollow
Daniel Claes, University of Nebraska-LincolnFollow
Kayle DeVaughan, University of Nebraska-Lincoln
Aaron Dominguez, University of Nebraska-LincolnFollow
Michael Eads, University of Nebraska-LincolnFollow
D. Johnston, University of Nebraska-LincolnFollow
Ioannis Katsanos, University of Nebraska-LincolnFollow
S. Malik, University of Nebraska-LincolnFollow
Gregory Snow, University of Nebraska-LincolnFollow
D0 Collaboration

Date of this Version

2011

Citation

PHYSICAL REVIEW D 84, 052007 (2011); DOI: 10.1103/PhysRevD.84.052007

Comments

Copyright 2011 American Physical Society

Abstract

We present an updated measurement of the anomalous like-sign dimuon charge asymmetry A^b_Sl for semileptonic b-hadron decays in 9.0 fb-1 of pp collisions recorded with the D0 detector at a center-of-mass energy of √s= 1.96 TeV at the Fermilab Tevatron collider. We obtain A^b_sl = (-0.787 ± 0.172 (stat) ± 0.093 (syst)) %. This result differs by 3.9 standard deviations from the prediction of the standard model and provides evidence for anomalously large CP violation in semileptonic neutral B decay. The dependence of the asymmetry on the muon impact parameter is consistent with the hypothesis that it originates from semileptonic b-hadron decays.